An interface declaration may be preceded by interface modifiers:
InterfaceModifiers:
InterfaceModifier
InterfaceModifiers
InterfaceModifier InterfaceModifier: one of
public abstract
The access modifier public
is discussed in §6.6. A compile-time error occurs if
the same modifier appears more than once in an interface declaration.
Every interface is implicitly abstract
. This modifier is obsolete and should not
be used in new Java programs.